A camshaft adjuster of this type including a central locking mechanism is already known from the prior art DE 10 2013 204 928 A1. In a camshaft adjuster of this type, the rotor is not only rotatable with respect to the stator within the chambers but is also fixable in a defined position, for example to make it easier to restart the engine. The chambers of the camshaft adjuster are supplied directly from an oil pump via a line. Relatively large and heavy oil pumps are required for this purpose to generate a sufficient volume flow to completely fill the enlarging working chambers in the camshaft adjuster with oil. If this does not take place, an underpressure may occur in the working chamber, whereby air is sucked into the camshaft adjuster. Due to the compressibility of air, the rotor is then no longer sufficiently hydraulically clamped in the chambers, so that vibrations may occur, which may impair the operation of the internal combustion engine and increase the consumption of the internal combustion engine and increase wear on the camshaft adjuster.
A camshaft adjuster is furthermore already known from the prior art, for example from EP 2 478 189 B1, in which a hydraulic accumulator is provided, a four-way valve being provided between the oil pump and the camshaft adjuster, which makes it possible to fill the chambers of the camshaft adjuster either directly via the oil pump or via the hydraulic accumulator. However, the disadvantage of this approach is that no central locking mechanism is provided.